Plaque to be installed 23rd August 2019 on York Observatory, Museum Gardens, York YO30 7BH

The son of a Pocklington shoemaker, the self-educated Thomas Cooke would become one of the leading optical instrument makers in England, supplying the royal family and designing, in its day, the largest telescope in the world. Cooke’s telescope of 1850 is now housed in York Observatory.

York Observatory

Born in Allerthorpe in the East Riding of Yorkshire on 8 March 1807, Thomas Cooke went to Pocklington National School for about two years before he became apprenticed to his father, James Cooke, who was a shoemaker. However, Thomas did not take to his father’s trade; he wanted to become a seaman but, as his mother did not approve of this choice of career, he studied navigation instead, educating himself in geometry and mathematics.

At the age of 17, Thomas became a teacher at the local school in Skirpenbeck, near Stamford Bridge, where he met his future wife. In 1829, at the age of 22, he moved to York and taught mathematics at the Revd Mr Shapkley’s school in Micklegate. To supplement his income, in the evenings he tutored the sons of gentlemen. He married his childhood sweetheart, Hannah Milner, in St Maurice’s Church on the corner of Monkgate and Lord Mayor’s Walk, York on 9 September 1831.

First reflecting telescope

Thomas studied optics in his spare time and began constructing a 6-inch diameter reflecting telescope. He cast the metal reflector himself using an amalgam of two parts of copper and one part tin but, as he was polishing it, the casting broke. There was, however, a large enough piece remaining which he ground down to a diameter of 31/2 ins from which he manufactured his first reflecting telescope.

Because the copper and tin alloy was so brittle, he decided to make his future reflectors using glass and, in the course of time, he succeeded in constructing a 4-inch refractor telescope with excellent definition. This telescope was bought, later, by Professor John Phillips (1800-74), Secretary and Keeper of the Yorkshire Museum and a member of the Yorkshire Philosophical Society. Phillips was a supporter of Thomas’s work and encouraged him to make other optical devices commercially.

Thomas and Hannah had seven children, five of whom were boys. Their first child, James Alfred, was born in 1832, but he died prematurely in 1839. The second child was Edwin (1833-75) followed by Charles Frederick (1835-98) and Thomas (1839-1919) who subsequently joined their father in his instrument-making business.

Stonegate shop

With the assistance of a loan of £100 from his wife’s uncle, Joseph Milner, in 1836 Thomas opened a shop at No.50 Stonegate, now renumbered No.18. Hannah looked after the shop, and at the rear of the premises were his workshops where instruments were repaired or made to order. One of Thomas’s first tasks was to make his own screw-cutting machine and this was to serve him for many years to come. He was now ready to undertake commissions for building telescopes, the first of which was a 41/2-ins aperture equatorial commissioned by William Gray, a leading York solicitor. Gray’s telescope was a great success and established Thomas as a scientific instrument maker.

By 1851 he had moved into larger premises at No.12 Coney Street where he employed four men and an apprentice. He was not only an optician but had mechanical abilities as well; amongst other things, he manufactured turret clocks for church towers and public buildings. He was commissioned by Hugh Pattinson of Newcastle to make an even larger 71/4-inch telescope.

Buckingham Works

The business must have been prospering because, in 1855, T. Cooke & Sons, with support from William Gray, purchased land on Bishophill on which to build the extensive Buckingham Works and apply factory methods of production to the manufacture of optical instruments. The same year, he exhibited at the Universal Exhibition in Paris where he was awarded a silver medal for his 6-inch, clock-driven telescope with an equatorial mount which allowed it to track celestial objects.

Thomas attended the Yorkshire Show in 1857, displaying a horizontal steam engine carriage as well as surveying instruments. In 1859 he was elected a member of the Royal Astronomical Society. His expertise came to the notice of the Royal Family and the following year he was invited by Prince Albert to Osborne House where he received an order for a 51/4 -inch telescope. By 1861 he was employing 26 men and 14 boys in his Buckingham Works and living at No.1 Bishophill. Thomas spent much time away from the factory in York, leaving the works in the care of Charles Frederick, who was a skilled mechanic, and his younger brother, Thomas who had trained as an optician.

1862 Great Exhibition

Robert Stirling Newall (1812-89) from Gateshead, a wealthy inventor and manufacturer of wire rope which he supplied to Cooke for church clocks, attended the 1862 Great Exhibition in London where he purchased two large discs of flint and crown glass from Chance Brothers. They cost £500 each and were of excellent optical quality and large enough to work into 25-inch lenses. Following a tendering process, Thomas Cooke was commissioned to make a telescope incorporating the lenses. But the price Thomas had quoted was too low and the delivery time of one year proved to be unrealistic. Inevitably everything took far longer than expected as special equipment had to be made to handle such large discs. Years passed before Thomas was satisfied with the lenses and Newall grew more and more impatient. The telescope was too large to assemble within the works as the length of the tube was 32 ft and it weighed 9 tons. It was still unfinished when Thomas died in 1868, leaving his estate to his wife Hannah. Newall tried to force Mrs Cooke and her two sons into liquidation, but they were rescued by Sir James Meek (1815-91), a wealthy industrialist and three times Lord Mayor of York (1855-6, 1865-6 and 1866-7).

The firm was then sold on to James Wrigglesworth (1825-88) who had been a close friend of Thomas Cooke and had sold him a 6-ins refractor in 1853. In his will, Wrigglesworth offered his son Robert the option to buy the Buckingham Works with its house, engines and machinery for £4,000. It seems likely that Robert exercised this option as he was a partner until the business became a limited company in 1897 and, thereafter, was a director.

Newall’s telescope was completed in 1871. Unfortunately, due to the industrial pollution of the Victorian age, the night-time atmospheric conditions in Gateshead were so poor that it was seldom used. Following Newall’s death in 1889, the telescope was transferred to the University of Cambridge where Newall’s son, Hugh Frank (1857-1944), was the Observer and, later, Professor of Astrophysics. In 1957 it was donated to the National Observatory of Athens at Penteli in Greece.

Transit telescopes and rotating domes

The firm took a stand at the 1862 Great Exhibition in London and was awarded two First Class Medals and received a large order from Lt Colonel Strange of the East India Company for 16 theodolites: the first of many orders to follow including two large transit telescopes for longitude observations in India. An order was received in 1882 for a rotating dome for Greenwich Observatory with an openable panel for night-viewing and, the following year, a further dome was supplied to James Wrigglesworth for his telescope in Scarborough. By the end of the century, Thomas Cooke’s domes had been built in countries throughout the world.

In 1882 work began on the Forth Bridge to carry the railway to the north of Scotland from Edinburgh. It was one of the major engineering projects of the century and the bridge would become an icon of Scotland. At a conference held in York in 1881, the Forth Bridge Railway Committee was set up, a partnership between four railway companies: the North British Railway, Midland Railway, North Eastern Railway and the Great Northern Railway. T. Cooke & Sons supplied equipment to the contractors, modifying 12-inch theodolites, introducing a downward-pointing telescope instead of a plumb bob and other refinements including the method of measuring the reflected line of sight. Thomas’s widow, Hannah, died on 21 September 1884 and her son Charles Frederick retired from the business in 1884 in favour of Alfred Taylor (1863-1940).

Thomas Cooke’s catalogues of the time illustrate a large range of products including small telescopes, binoculars, microscopes, surveying instruments, telegraphic equipment, steam engines, machine tools, and a pneumatic dispatch system to send documents round large offices. Major customers included the rapidly-expanding railway companies, the War Office, the Post Office and the Admiralty.

Towards the end of the 1880s, however, the firm was in financial difficulties to such an extent that, by 1891, the bank refused to increase their overdraft facilities to purchase more property. By 1893, the overdraft had increased to £6,000. The downturn in orders was possibly due to the trade depression at that time. Despite this, the Buckingham Works was expanded to cover 23,000 sq.ft; an office was opened in Victoria Street, London in 1895; and, in 1899, an overseas office was established in Cape Town to supply theodolites to the gold and diamond mines in Johannesberg.

Optical munitions

With the American Civil War of 1861, the Franco Prussian War and the Boer War, followed by the First World War, there was a growing demand for what were known as optical munitions such as rangefinders and gunsights. Wartime demands led to further expansion with the creation of “No. 2 Factory” on the corner of Bishophill Junior and Senior. This large building, now converted to residential accommodation, was designed by Walter Brierley. It is the only part of the original factory to survive. In 1915 Vickers acquired a 70 per cent holding in the company which concentrated increasingly on military equipment. The No.2 Factory was sold in 1919. In 1922 Cooke’s bought Troughton & Simms and became Cooke, Troughton & Simms Ltd operating under the Vickers’ banner. In 1939 a new factory was built on a 5.5-acre site on Haxby Road where it remained until its final closure in 1980.

York Observatory

Built 1831-2, York Observatory is the oldest working observatory in Yorkshire. Its cone-shaped roof – simpler and more economical to build than a hemispherical one – incorporates doors which can be opened for night-time use of the telescope. During the 19th century, there were huge advances in the science of astronomy and the subject was of national interest. At the inaugural meeting of the British Association for the Advancement of Science, which took place at the Yorkshire Museum in 1831, the vice president of the Royal Astronomical Society, Dr Pearson, said that, if an observatory were to be built in York, he would supply the telescope. Two years later he fulfilled his promise and also provided other scientific instruments including a clock.

Partly due to the construction of a national railway network and the introduction of a railway timetable, the 19th century saw the introduction of standardised time-keeping throughout the country. In York, the observatory served as a central point where watches and clocks could be set to the time which has always been four minutes and twenty seconds behind Greenwich Mean Time. The sum of sixpence was charged for checking timepieces against Dr Pearson’s clock which tells the time based on observations of the positions of stars.

After the Second World War, the building was neglected and the original telescope disappeared. Following a public campaign which raised the sum of £50,000, the observatory was restored and reopened in 1981. Dr Pearson’s clock is still in situ and the original telescope has been replaced by one made by Thomas Cooke in 1850. Today the observatory is open regularly to the public, staffed by volunteers on behalf of York Museums Trust. For opening times and special star-gazing events, visit

Anita McConnell, Instrument Makers to the World, A History of Cooke, Troughton & Simms (York: William Sessions, 1992), pp50-89

Samuel Smiles, Men of Invention and Industry (London, 1st edition 1885, now available in a free Kindle edition)

© Geoffrey Geddes